Silver halide emulsion containing 1.2-glycol as sensitizer and antifoggant

ABSTRACT

A photographic silver halide light-sensitive emulsion is enhanced in sensitivity without an attendant increase in fog by addition to the silver halide emulsion of a 1,2-glycol of the general formula WHEREIN R1, R2 and R3 represent a hydrogen atom or an alkyl group, and R4 represents a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, an aryloxyalkyl group, or an allyloxyalkyl group.

United States Patent Sonoda et al.

[ 51 Mar. 21, 1972 SILVER HALIDE EMULSION CONTAINING 1.2-GLYCOL AS SENSITIZER AND ANTIFOGGANT Inventors: Minoru Sonoda; Nobuo Yammamoto;

Akikazu Mikawa, all of Kanagawa, Japan Fuji Photo Film Co., Ltd., Ashigara- Kamigun, Kanagawa, Japan Filed: July 9, 1969 Appl. No.2 840,477

Assignee:

Int. Cl. ..G03c 1/28, G030 1/34 Field of Search. ..96/l07, 109

References Cited UNITED STATES PATENTS 12/1962 Chiesa et a1.

3,294,540 12/1966 Goffe ..96/l07 Primary Examiner-Norman G. Torchin Assistant Examiner-Won H. Louie, Jr. Attorney-Sughrue, Rothwell, Mion, Zinn & Macpeak [5 7] ABSTRACT A photographic silver halide light-sensitive emulsion is enhanced in sensitivity without an attendant increase in fog by addition to the silver halide emulsion of a 1,2-glycol of the wherein R R and R represent a hydrogen atom or an alkyl group, and R represents a hydrogen atom, an alkyl group. an aryl group, an alkoxyalkyl group, an aryloxyalkyl group. or e jl lssmyL rs rz-Am I. W

1 1 Claims, No Drawings SILVER HALIDE EMULSION CONTAINING LZ-GLYCOL AS SENSITIZER AND ANTIFOGGANT BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic silver halide light-sensitive element and a method for preparing it. More particularly, the present invention relates to a photographic silver halide light-sensitive element having a silver halide emulsion layer containing a compound having a sensitizing action and an antifogging action simultaneously and also a method for the preparation thereof.

2. Description of the Prior Art In order to improve the sensitivity of a photographic silver halide emulsion, the silver halide emulsion is subjected to chemical ripening, i.e., a sulfur sensitization, reduction sensitization, or gold sensitization. Various sensitizers can be added to the photographic emulsion after the application of chemical ripening.

However, as is well known, when the sensitivity of a photographic silver halide emulsion is increased, the formation of fog is also increased. Such fog is highly undesirable for photographic light-sensitive elements and for eliminating or reducing fog various studies have been made. For example, it has been attempted to reduce the formation of fog by adding an antifoggant or a stabilizer to a photographic silver halide emulsion which has been chemically ripened.

However, by such a conventional method, it is impossible to suppress completely the formation of fog. Also, by this method the photographic properties of the emulsion are adversely influenced by the addition of such additives.

Thus, an object of the present invention is to provide a photographic silver halide emulsion which is sensitized without an attendant increase in fog.

Another object of this invention is to provide photographic silver halide light-sensitive element having a photographic layer of the above photographic silver halide emulsion.

Still another object of this invention is to provide a method of preparing the aforesaid photographic silver halide emulsion and also the aforesaid photographic silver halide light-sensitive element.

SUMMARY OF THE INVENTION The above-mentioned objects of this invention can be achieved by incorporating in a silver halide emulsion a a 1,2- glycol represented by the general formula HOCHzCHzOH,

CHa-CH-CH-OH CHaCHr-CH-CHzOH CHz-CH-CHZOH Compound (a):

Compound (b):

Compound (c):

Compound (d):

Compound (e):

Ha Ha Compound (g): CHa(CHz)aCH-CHOH Compound (h): @CEL-CHMH Compound (I):

OH OCH;

The above compound used in this invention acts as a sensitizer and an antifoggant simultaneously and gives an excel lent sensitizing effect as compared with conventional sensitizers as well as reduces the formation of fog which has been considered to be increased with an increase in sensitivity. Accordingly, the silver halide emulsion containing the compound and the photographic silver halide light-sensitive element having the silver halide emulsion layer of this invention are excellent in such points that the sensitivity is high and the formation of fog is less as compared with conventional emulsions and elements.

The compound of this invention may be added to a silver halide emulsion subjected to chemical ripening together with other additives as usually practiced or may be added to a silver halide emulsion subjected to physical ripening by a conventional method. However, better results can be obtained when the compound is added to a silver halide emulsion at the beginning of chemical ripening.

The amount of the compound shown above to be added to a silver halide emulsion is influenced by a desired effect, the degree of ripening thereof, the kind of the silver halide emulsion and the like, but in general, preferably about 2-100 g., particularly 5-50 g. of the 1,2-glycol are added per mole of silver halide in the emulsion. The compound can also be used together with photographic additives usually employed, such as, an optical sensitizer, a wetting agent, a hardening agent, a

' plasticizer, etc., without injuring the photographic properties.

EXAMPLE 1 To a gelatino silver iodobromide emulsion for high speed negative photographic film washed with water (7 mole percent Agl and 200 g. of gelatin per one mole of silver iodobromide) was added 2,3-butanedio1 (Compound (b)). A second and a third emulsion were likewise prepared incorporating 1,2-butandiol (Compound (c)), and pinacol (Compound (f)) respectively. The resulting silver halide emulsions were subjected to a second ripening by sulfur and gold sensitizations at 52 C. Then, after adding a suitable amount ofchromium alum and saponin, the coating compositions thus prepared were applied to cellulose acetate films so that the amount of silver coated became 45 mg./ l sq. cm. and dried. For comparison, a control sample was prepared by the aforesaid procedure but without adding the compound of this invention.

The photographic light-sensitive films thus prepared were exposed by using a NSG-ll sensitometer and developed for 7 minutes at 20 C. in a developer having the following compositron:

p-Aminophenol 2.0 g. Sodium sulfite (anhydrous) 100 g. Hydroquinone g. Borax 2.0 g. Water to make 1 liter The results are shown in the following table. in which the sensitivity shown is a relative value calculated from the exposure amount giving a density of fog 0.3 assuming the sensitivity of the control sample ripened for 50 minutes being 100.

Concentration by gJrnole ofsilver iodobromide; A: sensitivity; B: fogt From the above results, it is seen that the photographic silver halide emulsion containing the additive of this invention had a high sensitivity and gave less formation offog.

EXAMPLE 2 Two separate silver iodobromide emulsions were prepared (1.5 mole percent Agl and 150 g. of gelatin per one mole of silver iodobromide) for high-speed X-ray photographic film, and 1,2-hexanediol (Compound (g)), and l-phenyl-l,2- ethanediol (Compound (h)) were added to the respective emulsions. These emulsions were then subjected to second ripening by sulfur-gold sensitization at 53 C. after adding a suitable amount of chromium alum and saponin, the silver halide emulsions thus prepared were applied to a cellulose acetate film so that the amount of silver applied became 55 mg./100 sq. cm. and dried. For comparison, a control sample was prepared by the same procedure as above without employing the compound of this invention. The photographic films thus obtained were exposed by using a NSG-ll sensitometer and developed for 4 minutes at C. in a developer having the composition as follows:

P-Aminophenol 410 g. Sodium sulfite (anhydrous) 60.0 g. Hydroquinone 10.0 g. Sodium Carbonate (anhydrous) 53.0 g. Potassium Bromide 2.5 g. Water to make 1 liter The results are shown in the following table, in which the sensitivity shown is a relative value calculated from the exposure amount giving the density of fog 0.3 assuming the sensitivity of the control sample ripened for 125 minutes being 100.

Compound Amount Ripcning Period min. min. 155 min.

A B A B A B None (Control) 100 0.11 126 0.13 0.17 (g) 18.3 129 0.06 148 0.08 160 0.12 (h) 11.7 111 0.09 133 0.10 0.13

Concentration by g./mole ofsilver iodobromide; A: sensitivity; 8: fog.

From the above results it is seen that the photographic silver halide emulsion containing the additive of this invention has a higher sensitivity and less fog than the control sample.

EXAMPLE 3 To separate gelatino silver iodobromide emulsions (7 mole percent Ag] and 200 g. of gelatin per one mole of silver iodobromide) for high speed negative photographic film subjected to sulfur sensitization and gold sensitization, were added 3-m-octyloxy-l,2-propanediol (Compound (k)), 3- aryloxy-l,2-propandiol (Compound (1)), 3-phenoxy-l,2-propandiol (Compound (m)), and 3-(2-methoxy)phenoxy-1,2- propanediol (Compound (0)) directly before coating, respectively. After further adding a suitable amount of chromium alum and saponin, the resulting silver halide emulsion was applied to a cellulose acetate film and dried. For comparison, a control sample was prepared by the same procedures as above without employing the additive of this invention.

These photographic films were exposed and developed as in Example 1, the results of which are shown in the following table in which the sensitivity was shown assuming the relative sensitivity ofgiving the density offog 0.3 being 100.

From the above results, it will be understood that the photographic silver halide emulsion of this invention prepared above had a high sensitivity and gave less fog.

What is claimed is:

1. A silver halide photographic emulsion containing a compound represented by the general formula wherein R R and R each represents one member selected from the group consisting of a hydrogen atom and an alkyl group, and R represents one member selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, an aryloxyalkyl group and an allyloxyalkyl group.

2. The silver halide photographic emulsion as claimed in claim 1 wherein said compound is selected from the group consisting of 2,3-butanediol, 1,2-butanediol, pinacol, 1,2-h'exanediol, 1-phenyl-l,2-ethanediol, 3-m-octyl-oxyl ,2- propanediol, 3-aryloxy-l,2-propanedio1, 3-phenoxy-l,2- propanediol and 3-phenoxyl ,2-propanediol.

3. The silver halide photographic emulsion as claimed in claim 1 wherein the amount of said compound is in the range t of from 2 to 100 g. per mol of silver halide.

4. A process for preparing silver halide photographic emulsion which comprises adding a compound represented by the general formula wherein R,, R and R each represents one member selected from the group consisting of a hydrogen atom and an alkyl group, and R represents one member selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, an aryloxyalkyl group and an allyloxyalkyl group.

6. The photographic silver halide light-sensitive element as claimed in claim 5 wherein said compound is selected from the group consisting of 2,3 butanediol, pinacol, l,2 hexanediol, 1-phenyl-l,2ethanediol, 3-m-octyloxyl ,2- propanediol and 3-phenoxy-l ,2-propanediol.

7. The silver halide photographic emulsion as claimed in claim 1, wherein the amount of said compound is in the range of from 5 to 50 g. per mol of silver halide.

8. The photographic silver halide light-sensitive element as claimed in claim 5, wherein said compound is present in an amount of from 2 to g. per mol of silver halide.

9. The photographic silver halide light-sensitive element as claimed in claim 8, wherein said compound is present in an amount of from 5 to 50 g. per mol of silver halide.

10. The silver halide photographic emulsion as claimed in claim 1, wherein said compound is selected from the group consisting of and 11. The photographic silver halide light-sensitive element as claimed in claim 5, wherein said compound is a member selected from the group consisting of 

2. The silver halide photographic emulsion as claimed in claim 1 wherein said compound is selected from the group consisting of 2, 3-butanediol, 1,2-butanediol, pinacol, 1,2-hexanediol, 1-phenyl-1,2-ethanediol, 3-m-octyl-oxy-1,2-propanediol, 3-aryloxy-1,2-propanediol, 3-phenoxy-1,2-propanediol and 3-phenoxy-1,2-propanediol.
 3. The silver halide photographic emulsion as claimed in claim 1 wherein the amount of said compound is in the range of from 2 to 100 g. per mol of silver halide.
 4. A process for preparing silver halide photographic emulsion which comprises adding a compound represented by the general formula wherein R1, R2 and R3 each represents one member selected from the group consisting of a hydrogen atom and an alkyl group, and R4 represents one member selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, an aryloxyalkyl group and an allyloxyalkyl group, to a physically ripened silver halide emulsion added at the beginning of chemical ripening.
 5. A photographic silver halide light-sensitive element comprising a support having coated thereon at least one silver halide emulsion layer containing a compound represented by the general formula wherein R1, R2 and R3 each represents one member selected from the group consisting of a hydrogen atom and an alkyl group, and R4 represents one member selected from the group consisting of a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, an aryloxyalkyl group and an allyloxyalkyl group.
 6. The photographic silver halide light-sensitive element as claimed in claim 5 wherein said compound is selected from the group consisting of 2,3 butanediol, pinacol, 1,2-hexanediol, 1-phenyl-1,2-ethanediol, 3-m-octyloxy-1,2-propanediol and 3-phenoxy-1,2-propanediol.
 7. The silver halide photographic emulsion as claimed in claim 1, wherein the amount of said compound is in the range of from 5 to 50 g. per mol of silver halide.
 8. The photographic silver halide light-sensitive element as claimed in claim 5, wherein said compound is present in an amount of from 2 to 100 g. per mol of silver halide.
 9. The photographic silver halide light-sensitive element as claimed in claim 8, wherein said compound is present in an amount of from 5 to 50 g. per mol of silver halide.
 10. The silver halide photographic emulsion as claimed in claIm 1, wherein said compound is selected from the group consisting of
 11. The photographic silver halide light-sensitive element as claimed in claim 5, wherein said compound is a member selected from the group consisting of 